Question

Forskolin is a drug used by scientists to render adenylyl cyclase (AC) constitutively (always) active. What will this do to to PKA levels and IP3 levels?

a) increase PKA
b) increase IP3
c) no effect on PKA
d) no effect on IP3

Answer 1

Forskolin will increase PKA levels and have no effect on IP3 levels.

Step-by-step explanation:

Forskolin, a drug used to activate adenylyl cyclase constitutively, would increase PKA levels and have no effect on IP3 levels.

Forskolin activates adenylyl cyclase, which increases cAMP and subsequently increases PKA activity. It does not affect IP3 levels since IP3 production is not linked to cAMP or AC activity.

Adenylyl cyclase is responsible for converting ATP to cyclic AMP (cAMP). By activating adenylyl cyclase with forskolin, there would be an increase in cAMP levels. Increased cAMP levels would then activate protein kinase A (PKA), leading to increased PKA levels.

On the other hand, forskolin does not directly interact with IP3 or affect IP3 levels. Therefore, there would be no effect on IP3 levels.

Answer 2

Both the PKA and IP3 levels increases. Hence, the correct answer is a and b.

Step-by-step explanation:

Forskolin refers to a drug that increases the levels of cAMP or cyclic AMP by stimulating the enzyme adenylyl cyclase. The cAMP is an essential secondary messenger that ensures proper biological response of cells to hormones and other signals and also takes part in communication between the cells.

When Forskolin increases the levels of cAMP, it will stimulate the enzyme PKA or protein kinase A and at the same time also enhances the intracellular concentration of Ca2+ and IP3 (inositol 1,2,5 triphosphate).